We have studied 16 patients diagnosed of social phobia among the hospitalized patients for 1 year, from September 1994 to August 1995, to evaluate whether serial phobic symptoms are the prodromal symptoms of the other psychiatric disorder or concomitant disorder. The results were as follows; 1) In the subject of this study, the mean age of onset of social phobic symptoms was 17.3, and the mean age of inital hospital visit was 27.4. 2) The proportion of offensive type was higher than the simple type : 7 cases of the subjects classified as simple type, 9 cases as offensive type. 3) According to the type of social phobia, they developed different type of psychiatric disorder. Majority of patients with simple type had final diagnosis of mood disorder. Patients with offensive type had schizophrenia spectrum disorder, such as schizophrenia, delusional disorder, and schizophrenia, personality disorder. 4) Social phobic symptoms have taken various courses according to the final diagnosis. In the patients who developed major depression and delusional disorder, social phobic symptoms have not been changed during the course. Patients with the final diagnosis of schizophrenia and schizotypal personality disorder have showed various social phobic symptoms. In the patients with the final diagnosis of bipolar disorder, their social phobic symptoms disappeared with improvement of depression.